1. Field of the Invention
The present invention relates to a high voltage spark gap switch wherein a gas insulated self-firing spark gap operates in the megavolt range.
2. Description of the Prior Art
A spark gap switch is useful in the output stages of a high voltage particle accelerator to switch the electrostatic energy stored on a pulse forming line (PFL) through the machine's diode. When an accelerator is repetitively pulsed at rates ranging from 1 to hundreds of pulses per second, the gas in the switch must completely recover its dielectric strength between pulses to withstand the subsequent PFL charge cycle voltage up to the self-fire level. The break-over of the spark gap must occur at identically the same voltage on each pulse. The condition of repeatable self-firing at a predetermined voltage is defined as stable spark gap operation.
The Sheets U.S. Pat. No. 3,551,737, discloses an electrode which has an opening therein and in which only a minor portion of the vortically flowing gas is drained from an arc chamber through the opening. The gas vortex stabilized radiation source includes electrodes 10, 11 and a powder gas source 33. Gas is supplied to the chamber 17 and is recirculated through the heat exchanger 22 and the pump 23 back into the chamber. The annular holes 24 generate a vortex effect to improve power handling capabilities. The vortex gas flow is designed to stabilize the arc discharge in the tube.
Thouret et al, U.S. Pat. No. 3,474,278, disclose an arc pressure lamp with an internal gas circulation having electrodes 18 and 48. Electrode 18 is hollow for the purpose of cooling the electrode assembly. The lamp disclosed by Thouret et al is designed to provide an intense steady light source.
The Van Ornum et al U.S. Pat. No. 3,469,143, discloses an electric arc light source having an undercut recessed anode. The anode includes a recess or opening 45 which provides the high efficiency and arc stability in addition to long electrode life at high power levels.
Van Ornum et al, U.S. Pat. No. 3,447,013, disclose a device substantially similar to U.S. Pat. No. 3,469,143. The electrode 10 includes a shroud 19 disposed around the surface thereof. The electrode 11 includes an opening through the central portion thereof. The device provides a vortex-stabilized radiation source wherein the arc is stable and readily controllable while major amounts of gas are drained from the peripheral region of the arc chamber for purposes of cooling the envelope.
Haslund, U.S. Pat. No. 3,543,076, discloses aerodynamic arc lamp electrodes. The arc lamp electrodes are aerodynamically shaped to provide an improved and stable light source at high power levels for an extended operating lifetime. A gas is circulated in a recirculating flow pattern which optimizes heat transfer, stabilizes the arc and controls deposition of vaporized electrode particles.